The present invention involves apparatus, systems and methods for erecting wind turbine assemblies at offshore locations.
The use of offshore wind turbines is becoming an increasingly feasible and desirable form of power generation. In implementing the concept of windmills, the larger the turbine rotor, the more power generated. Thus, massive structures are being contemplated and built.
Some of the challenges associated with this technology involve the installation of huge wind turbine structures at offshore locations. Currently available seagoing vessels and techniques are not believed not to be well-suited or cost effective for handling and installing these structures. For example, current technology would require the use of a very heavy and long stick-lift vessel or multiple lifting/loading vessels. For another example, lifting a fully assembled turbine assembly with existing technology would place unacceptable levels stress on the turbine nacelle. If installed separately with existing techniques, the turbine rotor and nacelle would necessarily be installed at heights unfamiliar in the offshore industry.
It should be noted that the above-described concerns are only examples and may vary depending upon the situation. Moreover, there may be other or different concerns. Merely by mentioning the above concerns, it is not intended that each claim of this patent be limited to address or exclude each such concern. Accordingly, none of the appended claims should be limited in any way by the above discussion, or construed to address or exclude the cited concerns, except and only to the extent as may be expressly stated in a particular claim.
There remains a need for apparatus, systems and methods having one or more of the following attributes, capabilities or features: solves problems associated with installing offshore wind turbines caused by existing methods and apparatus; provides for installation of a fully or partially assembled offshore wind turbine without the need for performing a dual lift, utilizing a very heavy and long stick-lift vessel, placing undue stress on the turbine nacelle during lifting (necessitating the need for spreader bars, etc.), or any combination thereof; eliminates the need for a specialized derrick barge for lifting and installing offshore wind turbines; significantly reduces installation time of offshore wind turbines; uses a pin-assisted up-righting method rather than a conventional lift; prevents out-of-plane loading and excessive stress on components during up-righting; allows the use of a single simple barge for performing foundation installation, turbine transport, erection and final fit-out including weld out, electrical installation and installation of ancillaries, repair, maintenance and removal of wind turbines, or any combination thereof; saves significant expense associated with up-righting offshore wind turbines; provides a simple and cost effective apparatus, system and method for offshore up-righting of wind turbines; provides effective offshore wind turbine installation with the use of existing equipment and/or removable components; or any combination thereof.